An agricultural work machine may comprise any type of work vehicle, such as a work vehicle with its own traction drive (e.g., drive axle with drive wheels) or a work vehicle without its own drive (e.g. a trailer). Example work vehicles may include agricultural work machines, such as field choppers or tractors, which may or may not include additions such as manure spreaders, seeders, spraying devices, separators, rakes or the like.
Various processes of an agricultural work machine may run automatically or semi-automatically, such as, among other things, the operation and control of a majority of the working assemblies of the work machine. A working assembly may comprise a component of the work machine that supports or performs an agricultural task, and consequently consumes power. Attachments for the work machine may include the aforementioned additions (e.g., manure spreaders, seeders, spraying devices, separators, rakes or the like) or may include reels or cutting units, or the front linkage for raising and lowering the attachments.
The agricultural work machines may typically have an internal combustion engine, such as a diesel motor, as the collective drive for the working assemblies and the traction drive. In this regard, the power supplied by the internal combustion engine may be supplied in part to the traction drive and in part to the respective working assembly (in the event that the work machine has a traction drive).
The power requirement of a working assembly may vary dependent on the situation in which the agricultural work operates. For example, during a harvesting process, the working assembly may require more power in a field having a relatively dense crop than in a field having a less dense crop or in the headland. Thus, for purposes of power conservation and reduction of wear, the maximum available power of the internal combustion engine may be automatically reduced.
DE 10 2008 020 497 A1 describes a regulating concept, in which the internal combustion engine that has a different performance characteristic (motor characteristic). The internal combustion engine is automatically operated in different power settings via the regulating device depending on the actual power requirements of the working assembly. The performance characteristics of the power settings differ in terms of the maximum power of the internal combustion engine, which is normally reached in the various power settings with the same rotational rate.
For example, if a harvester is driven in a headland, the regulating device, because of the reduced power requirements of the respective working assembly, increases the rotational rate at the drive shaft of the internal combustion engine, and shifts the internal combustion engine thereupon, potentially multiple times successively, to a lower power setting having a lower maximum power. As a result, the rotational rate of the drive shaft, and potentially the torque, is reduced. After passing through the headland, the harvester drives back into the crop that is to be harvested while the internal combustion engine is still operated in the lower power setting, resulting in the power requirements of the respective working assembly again increasing. As a result, the rotational rate of the drive shaft is reduced, and the regulating device causes a shifting of the internal combustion engine into a higher power setting, potentially likewise via numerous power settings, in order that the internal combustion engine can again provide a higher power.